docs: def add(self, entry):
          """
          Override this to influence the mechanics of the Archive.
          Assumes entry is a seq beginning with (nm, pth, ...) where
          nm is the key by which we'll be asked for the object.
          pth is the name of where we find the object. Overrides of
          get_obj_from can make use of further elements in entry.
          """
          if self.os is None:
              import os
              self.os = os
          nm = entry[0]
          pth = entry[1]
          pynm, ext = self.os.path.splitext(self.os.path.basename(pth))
          ispkg = pynm == '__init__'
          assert ext in ('.pyc', '.pyo')
          self.toc[nm] = (ispkg, self.lib.tell())
          f = open(entry[1], 'rb')
          f.seek(8)  # skip magic and timestamp
          self.lib.write(f.read())